Mapping Subsets of Scholarly Information

We illustrate the use of machine learning techniques to analyze, structure, maintain, and evolve a large online corpus of academic literature. An emerging field of research can be identified as part of an existing corpus, permitting the implementation of a more coherent community structure for its practitioners.Comment: 10 pages, 4 figures, presented at Arthur M. Sackler Colloquium on "Mapping Knowledge Domains", 9--11 May 2003, Beckman Center, Irvine, CA, proceedings to appear in PNA

The Structure of Ethnic Inequality and Ethnic Voting

Why do some ethnic groups vote along ethnic lines while others do not? In this article, we theorize that the level of ethnic voting depends, partially, on how ethnicity interacts with economic cleavages. Specifically, we argue that between–ethnic group inequality (BGI) increases ethnic voting and that its effect strengthens as within–ethnic group inequality (WGI) decreases. We thus posit that the full structure of ethnic inequality, not only between-group differences, matters for ethnic voting. After presenting our argument, we conduct the first cross-national test of whether the effect of betweengroup inequality on ethnic voting is conditional on the level of inequality within ethnic groups. Our analysis employs group-level data on 200 ethnic groups from65 countries. We find strong support for our hypothesis: BGI increases ethnic voting, but its effect is conditional on WGI

Automated measurement of Drosophila wings

BACKGROUND: Many studies in evolutionary biology and genetics are limited by the rate at which phenotypic information can be acquired. The wings of Drosophila species are a favorable target for automated analysis because of the many interesting questions in evolution and development that can be addressed with them, and because of their simple structure. RESULTS: We have developed an automated image analysis system (WINGMACHINE) that measures the positions of all the veins and the edges of the wing blade of Drosophilid flies. A video image is obtained with the aid of a simple suction device that immobilizes the wing of a live fly. Low-level processing is used to find the major intersections of the veins. High-level processing then optimizes the fit of an a priori B-spline model of wing shape. WINGMACHINE allows the measurement of 1 wing per minute, including handling, imaging, analysis, and data editing. The repeatabilities of 12 vein intersections averaged 86% in a sample of flies of the same species and sex. Comparison of 2400 wings of 25 Drosophilid species shows that wing shape is quite conservative within the group, but that almost all taxa are diagnosably different from one another. Wing shape retains some phylogenetic structure, although some species have shapes very different from closely related species. The WINGMACHINE system facilitates artificial selection experiments on complex aspects of wing shape. We selected on an index which is a function of 14 separate measurements of each wing. After 14 generations, we achieved a 15 S.D. difference between up and down-selected treatments. CONCLUSION: WINGMACHINE enables rapid, highly repeatable measurements of wings in the family Drosophilidae. Our approach to image analysis may be applicable to a variety of biological objects that can be represented as a framework of connected lines

Using neighborhood observation to support public housing tenants’ empowerment

Although public housing is often described as a negative and stigmatized environment, tenants living in such an environment can cultivate a positive sense of community, which enhances their individual and collective well-being. The present study describes the second phase of a large action research, aiming to facilitate the empowerment of public housing\ud tenants acting as peer-researchers Following a Photovoice phase, this second phase focuses on the development and first implementation of a participatory observation method as a tool for evaluating their collective environment fit. A group of nine tenants contributed to\ud develop and later completed an observation grid. The observations were then discussed in decision-making sessions. The participatory observation method proved useful in supporting tenants in their reflection process, promoting the depiction of a nuanced portrait of their residential environment while also prioritizing capacity building. Results are currently used to inform an action phase in which tenants are taking increasingly more\ud power. Triangulating the results from multiple sites is needed to establish more firmly the added-value of this observation method in a larger research project. Key challenges and lessons learned are described in a reflective section, sharing experiential knowledge with researchers that consider using a similar method

Performance Measurements of Supercomputing and Cloud Storage Solutions

Increasing amounts of data from varied sources, particularly in the fields of machine learning and graph analytics, are causing storage requirements to grow rapidly. A variety of technologies exist for storing and sharing these data, ranging from parallel file systems used by supercomputers to distributed block storage systems found in clouds. Relatively few comparative measurements exist to inform decisions about which storage systems are best suited for particular tasks. This work provides these measurements for two of the most popular storage technologies: Lustre and Amazon S3. Lustre is an open-source, high performance, parallel file system used by many of the largest supercomputers in the world. Amazon's Simple Storage Service, or S3, is part of the Amazon Web Services offering, and offers a scalable, distributed option to store and retrieve data from anywhere on the Internet. Parallel processing is essential for achieving high performance on modern storage systems. The performance tests used span the gamut of parallel I/O scenarios, ranging from single-client, single-node Amazon S3 and Lustre performance to a large-scale, multi-client test designed to demonstrate the capabilities of a modern storage appliance under heavy load. These results show that, when parallel I/O is used correctly (i.e., many simultaneous read or write processes), full network bandwidth performance is achievable and ranged from 10 gigabits/s over a 10 GigE S3 connection to 0.35 terabits/s using Lustre on a 1200 port 10 GigE switch. These results demonstrate that S3 is well-suited to sharing vast quantities of data over the Internet, while Lustre is well-suited to processing large quantities of data locally.Comment: 5 pages, 4 figures, to appear in IEEE HPEC 201

The phase plane of moving discrete breathers

We study anharmonic localization in a periodic five atom chain with quadratic-quartic spring potential. We use discrete symmetries to eliminate the degeneracies of the harmonic chain and easily find periodic orbits. We apply linear stability analysis to measure the frequency of phonon-like disturbances in the presence of breathers and to analyze the instabilities of breathers. We visualize the phase plane of breather motion directly and develop a technique for exciting pinned and moving breathers. We observe long-lived breathers that move chaotically and a global transition to chaos that prevents forming moving breathers at high energies.Comment: 8 pages text, 4 figures, submitted to Physical Review Letters. See http://www.msc.cornell.edu/~houle/localization

Sex and gender role differences on stress, depression, and anxiety symptoms in response to the COVID-19 pandemic over time

IntroductionStress, depression, and anxiety symptoms have been reported during the pandemic, with important inter-individual differences. Past cross-sectional studies have found that sex and gender roles may contribute to the modulation of one's vulnerability to develop such symptoms. This longitudinal study aimed to examine the interaction of sex and psychological gender roles on stress, depression, and anxiety symptoms in adults during the COVID-19 pandemic.MethodsFollowing the confinement measures in March 2020 in Montreal, stress, depression, and anxiety symptoms were assessed every 3 months (from June 2020 to March 2021) with the Depression, Anxiety and Stress Scale among 103 females and 50 males. Femininity and masculinity scores were assessed with the Bem Sex Role Inventory before the pandemic and were added as predictors along with time, sex, and the interactions between these variables using linear mixed models.ResultsWe observed similar levels of depressive symptoms between males and females, but higher levels of stress and anxious symptoms in females. No effects of sex and gender roles on depressive symptoms were found. For stress and anxiety, an interaction between time, femininity, and sex was found. At the beginning of the pandemic, females with high femininity had more stress symptoms than males with high femininity, whereas females with low femininity had more anxiety symptoms 1 year after the confinement measures compared to males with low femininity.DiscussionThese findings suggest that sex differences and psychological gender roles contribute to heterogeneous patterns of stress and anxiety symptoms over time in response to the COVID-19 pandemic

Institutionalizing New Practices Using Lean Methodologies

K992 FHWA Program code M37A (Delphi Code 15X0445060)This document summarizes lean activities conducted through the Washington State Department of Transportation\u2019s (WSDOT) Accelerated Innovation Deployment (AID) project, \u201cDeploying Practical Solutions with Lean Techniques and Knowledge Management\u201d (PS AID Project). This report provides a summary of the processes used to map a high-level business process for Practical Solutions, capture information on challenges and opportunities, subsequent activities to improve select processes, and recommendations for using lean methodologies to support the deployment of Practical Solutions at WSDOT

Acoustic Emission from crumpling paper

From magnetic systems to the crust of the earth, many physical systems that exibit a multiplicty of metastable states emit pulses with a broad power law distribution in energy. Digital audio recordings reveal that paper being crumpled, a system that can be easily held in hand, is such a system. Crumpling paper both using the traditional hand method and a novel cylindrical geometry uncovered a power law distribution of pulse energies spanning at least two decades: (exponent 1.3 - 1.6) Crumpling initally flat sheets into a compact ball (strong crumpling), we found little or no evidence that the energy distribution varied systematically over time or the size of the sheet. When we applied repetitive small deformations (weak crumpling) to sheets which had been previously folded along a regular grid, we found no systematic dependence on the grid spacing. Our results suggest that the pulse energy depends only weakly on the size of the paper regions responsible for sound production.Comment: 12 pages of text, 9 figures, submitted to Phys. Rev. E, additional information availible at http://www.msc.cornell.edu/~houle/crumpling